Upper vent sill



FIG. 1 is a fragmentary top perspective view of the upper vent sill showing my design;

FIG. 2 is a top plan view thereof broken away to indicate indeterminate length;

FIG. 3 is bottom plan view thereof broken away to indicate indeterminate length;

FIG. 4 is a front elevational view thereof in which the rear elevational view is a mirror image of the front view;

FIG. 5 a right elevational view thereof broken away to indicate indeterminate length; and,

FIG. 6 is a left elevational view thereof broken away to indicate indeterminate length. 

The ornamental design for a upper vent sill, as shown and described. 